Metoda 4M – nowe zastosowanie spektroskopii mössbauerowskiej w klasyfikacji zrównoważonych chondrytów zwyczajnych

• Authors: Marek Woźniak , Łukasz Karwowski , Jolanta Gałązka-Friedman , Przemysław Duda , Martyna Jakubowska , Patrycja Bogusz

Title variants

EN

4M method – the new application of Mössbauer spectroscopy for classification of equilibrated ordinary chondrites

• Languages of publication: PL

Abstracts

EN

The 4M method aims to determine the type of equilibrated ordinary chondrite only on the basis of the Mössbauer spectrum of the investigated meteorite. Mössbauer spectrum of non-weathered ordinary chondrite is comprised of four sub-spectra: two doublets and two sextets. One of the doublets consists of a signal from iron present in olivine and the other consists of a signal from iron present in pyroxene. Sextets on the other hand, contain signals from magnetically ordered iron. One sextet is related to the metallic phase (kamacite, taenite), whereas the second is related to troilite. A third of doublets, which emerges in weathered ordinary chondrites, is related to products of the oxidation of iron present in metallic phase. The spectral areas of olivine, pyroxenes, metallic phase and troilite, which were obtained from Mössbauer spectrum are proportional to the number of iron atoms present in relevant mineral phases. Some Mössbauer groups were inspired by this fact to construct different methods to determine the type (H, L, or LL) of investigated meteorites (Gałązka-Friedman et al. 2019, Hyp. Inter. 241(1)). However, these methods, based on subjective criteria, were only qualitative. Our group elaborated a quantitative method, which is based on objective criteria. We called it the "4M method" (where M are derived from meteorites, Mössbauer spectroscopy, multidimensional discriminant analysis (MDA), Mahalanobis distance) (Woźniak et al. 2019). This method was using only the Mössbauer experimental data, to which it applied advanced statistical methods. The base, which was created from Mössbauer data, consisted of three clusters H, L, LL. These clusters were constructed with sets of 4-dimensional vectors. The vectors are comprised of spectral areas of Mössbauer spectrum: ol (value proportional to iron present in olivine), pyr (value proportional to iron present in pyroxene), met (value proportional to iron present in metallic phase), tr (value proportional to iron present in troilite). To determine the type of investigated ordinary chondrite, its ol, pyr, met and tr values with average values of variables obtained for clusters H, L and LL need to be compared. The comparison can be performed with the use of MDA and Mahalanobis distance. Once Mahalanobis distance of the investigated meteoriteis is known, the level of similarity to three types of ordinary chondrites can be calculated. Examples of such calculations were performed for seven ordinary chondrites: Goronyo, Carancas, New Concord, NWA 7733, Leoncin, Sołtmany and Pułtusk. They were made with the use of the new base composed of 62 non-weathered ordinary chondrites. All results obtained with the 4M method yielded results consistent with traditional mineralogical methods.

Keywords

EN

4M method; Cluster Analysis; Mahalanobis distance; Multidimensional Discriminant Analysis; Mössbauer spectroscopy; Principal Components Analysis; meteorites; meteorites classification; ordinary chondrites

Discipline

• PHYSICS: PHYSICS

• Publisher: Polskie Towarzystwo Meteorytowe
• Journal: Acta Societatis Metheoriticae Polonorum
• Year: 2020
• Volume: 11
• Pages: 125-140

Contributors

author

Marek Woźniak

• Uniwersytet Warszawski, Wydział Biologii

author

Łukasz Karwowski

• Wydział Nauk Przyrodniczych, Uniwersytet Śląski w Katowicach

author

Jolanta Gałązka-Friedman

• Politechnika Warszawska, Wydział Fizyki

author

Przemysław Duda

• Politechnika Warszawska, Wydział Fizyki

author

Martyna Jakubowska

• Politechnika Warszawska, Wydział Fizyki

author

Patrycja Bogusz

• Politechnika Warszawska, Wydział Fizyki

References

• Bogusz P., Gałązka-Friedman J., Brzózka K., Jakubowska M., Woźniak M., Karwowski Ł., Duda P., 2019, Mössbauer spectroscopy as a useful method for distinguishing between real and false meteorites, Hyperfine Interact., 240(1), ss. 11. doi:10.1007/s10751-019-1659-7
• Bogusz P., Maliszewki A., Duda P., Woźniak M., 2020, Z efektem Mössbauera na Marsie, Acta Soc. Metheor. Polon., 11, s. 7–30.
• Fredriksson K., Keil K., 1964, The iron, magnesium and calcium distribution in coexisting olivine and rhombic pyroxenes in chondrites, Journal of Geophysical Research, 69, s. 3487–3515.
• Gałązka-Friedman J., Woźniak M., Duda P., Jakubowska M., Bogusz P., Karwowski Ł., 2019a, Próby klasyfikowania chondrytów zwyczajnych przez zastosowanie spektroskopii mössbauerowskiej (Attempts of classification of ordinary chondrites by application of Mössbauer spectroscopy), Acta Soc. Metheor. Polon., 10, s. 23–28.
• Gałązka-Friedman J., Woźniak M., Bogusz P., Jakubowska M., Karwowski Ł., Duda P., 2019b, Application of Mössbauer spectroscopy for classification of ordinary chondrites – different database and different methods, Hyperfine Interact., 241(1), ss. 12. doi:10.1007/s10751-019-1661-0
• Koblitz J., 2012, MetBase. Meteorite data retrieval software, Version 7.3 (CD-ROM), Ritterhude, Germany.
• Krzanowski J., 2000, Principles of multivariate analysis: A user’s perspective, Oxford University Press, Oxford.
• Mahalanobis P.C., 1936, On the generalized distance in statistics, Proceedings of the National Institute of Sciences of India, 2, s. 49–55.
• Mason B.H., 1962, Meteorites, John Wiley and Sons, Inc., ss. 274.
• Morrison D.F., 1990, Multivariate statistical Methods, New York, NY, McGraw-Hill.
• Woźniak M., Gałązka-Friedman J., Duda P., Jakubowska M., Rzepecka P., Karwowski Ł., 2019, Application of Mössbauer spectroscopy, multidimensional discriminant analysis, and Mahalanobis distance for classification of equilibrated ordinary chondrites, Meteoritics & Planetary Science, 54(8), s. 1828–1839. doi:10.1111/maps.13314

• Document Type: article